Circuit breaker



April 15, 1947.

G. .J. EASLEY CIRCUIT BREAKER WITNESSES: INVENTOR Gilbert .[E'as/ey.

April 15, 1947. G. J. EASLEY 2,419,127

CIRCUIT BREAKER Filed March 11, 1944 2 Sheets-Sheet 2 183 I INVENTOR 2 Gi/berz J Easley.

Patented Apr. 15, 1947 2,419,127

UNITED STATES PATENT OFFICE CIRCUIT BREAKER Gilbert J. Easiey, Wilkinsburg', Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa. a corporation of Pennsylvania Application March 11, 1944, Serial No. 526,017

10 Claims. (01. 200-82) 1 2 This invention relates to circuit breakers and, closing of the breaker with rapid reversal of the more particularly, to circuit breaker operating switching movement of the breaker, the mean mechanisms of the pneumatic type. anism having an automatically operable valve for Circuit breakers for electrical power systems reducing the air pressure applied to the piston are desired which operate at very high speeds 5 on normal closing operations and for causing full and in Which the motion of the parts can be air pressure to be applied to the piston on quick quickly reversed, in order to obtain quick interreclosing operations, and having a bypass around ruption also quick reclosing of the electrical the automatic valve for quickly exhausting the circuit. When an operating mechanism of the air pressure back of the piston on opening oppneumatic type is employed for operating the cirerations. cuit breaker, back fluid pressure in the operat- Another object of the invention is the proing cylinder tends to retard the speed of the vision of a circuit breaker operating mechanism opening stroke of the piston. Dump valves have of the pneumatic type with an improved quickbeen employed for opening main exhaust ports acting inlet and exhaust valve device for admitto quickly exhaust the back fluid pressure for ting fluid to the operating cylinder and also for a portion of the opening stroke of the piston on rapidly and fully venting the cylinder to atmospneumatic trip-free operations. That is, when phere to permit high-speed operation and quick the breaker is closed in on a fault and it is necreversal of the breaker operating mechanism. essary to quickly exhaust the closing air from the Another object of the invention is the provision cyiinder to permit high-speed opening of the of a circuit breaker with an improved operating breaker. After the main exhaust port is closed mechanism of the pneumatic type capable of during the opening stroke, the fluid trapped back effecting high-speed opening and quick reclosing of the pis on retards the speed of the opening of the circuit breaker. stroke of the mechanism. The main dump valve The novel features that are considered charon exhaust valve does not operate on normal acteristic of the invention are set forth in paropening operations, and the fluid, at atmosphere ticular in the appended claims. The invention pressure, would be compressed during the openitself, however, both as to structure and opering stroke, thus retarding the opening moveation, together with additional objects and adment or the breaker mechanism. This trapped vantages thereof, will be best understood from fluid pressure is usually exhausted through the the following deta descriptmn Of 0118 bo inlet valve which admits fluid pressure to the ment thereof when read in conjunction with the cylinder. In modern fluid pressure operated ciraccompanying drawings, in which:

cuit breakers, the force required for normal clos- F i 1 s n em-13101131 View, partly in secing operations is substantially less during the first tion, of a circuit breaker operating mechanism, portion of th closing stroke than during the the circuit breaker being shown schematically. final portion of the closing stroke when the heavy Fig. 2 is a vertical sectional View of the circuit contact load is being overcome. For this reason breaker operating mechanism showing the valve it has heretofore been the practice to provide structure.

means for restricting the inlet passage to admit Fig. 3 is an enlarged horizontal sectional view the minimum fluid pressure required for normal taken substantially on line III-III of Fig. 2 showclosing operations. Such restricted passages do ing the. inlet valve, the throttle valve and the not provide adequate and sufiiciently rapid exseveral control pas es. haust flow of the trapped fluid pressure. This The present invention in Certain p ct s a results in undesirably retarding the speed of the further development and improvement of the owning operation of the bre k r, invention disclosed and claimed in the copendan object of the present invention is the proi s application of James M. Cumming and Henry vision of a circuit breaker with an improved ope al o. 445,83 filed June 5, 1942, now eratin mechanism of the pneumatic type ca- Patent No. 2,384,801, issued September 18, 1945, pable of effecting high-speed operation of the and assigned to the assignee o the present circuit breaker and quick reversal of the moving vention. parts Referring to Figs. 1 and 2 of the drawings, the Another object of the invention is the procircuit breaker operating mechanism comprises, vision of a circuit breaker embodying an opergencra1ly,amain casting H, an operating cylinder ating mechanism of the pneumatic type operl5 ln the casting, a piston ll movable in the able to produce normal closing and quick recylinder, a trip device indicated generally at 19 (Fig. 1), a control valve device 2i (Fig. 2) for admitting compressed air to the cylinder to effect closing movement of the piston ll, a valve 23 for controlling the air intake, an exhaust valve mechanism 25, and a latch mechanism indicated generally at 27 (Fig. 1).

The lower end of the cylinder I is closed by means of a closure member 29 suitably secured to the main casting iI, the upper end of the cylinder I5 being closed by a portion 33 of the casting. The piston I? includes an upwardly extending hollow tube 35 which slidably fits within an opening in the portion 33 of the casting II.

The tube is connected, at its upper end by means of a pivot pin M to a link 43, which, in turn, is conn cted at its upper end, by means of a pivot pin to a coupling 41 secured on the lower end of a breaker operatin rod 43. The operating rod .9 is connected by suitable linkage to the circuit breaker mechanism shown schematically at 5\. (Fig. 1) which may be an air breaker or an oil breaker of any conventional type. The breaker mechanism is biased to open position and actuated to open the breaker contacts by means of an accelerating spring 52.

The pivot pin 45 (Fig. 2) which connects link 43 to the coupling 41, extends beyond the sides of the coupling and is connected by means of suitable bearing members 5| to an operating lever 53 comprising a pair of spaced parallel levers. As shown in Fig. 1 the levers 53 are pivotally supported, at their right hand ends, by means of a pivot pin 55, on the upper end of a link 51 whose lower end is pivoted on a pivot pin 59 mounted in a pair of ears GI projecting outwardly and upwardly from the main casting I I.

The left hand ends (Fig. 1) of the levers 53 are rigidly connected by means of a rod 63 and are spaced apart by a roller 65 rotatably mounted on the rod 63 between the levers. The latch mechanism 2'. normally cooperates with the roller 65 to releasably restrain the breaker mechanism in closed position.

The latch mechanism 21 includes a main latch 67 pivotally supported on a pivot pin 69 mounted in projections H extending upwardly from the main casting Ii. The main latch 67 is biased to latching position by means of a spring I3 coiled around a rod i5 and compressed between a projection I! of the casting II and a washer I9 supported on the lower end of the rod '15 by a nut 8 I. The rod extends upwardly through a guide opening in the projection 'i'. and is pivotally connected at its upper end by m ans of a pivot pin 33 to the main latch 6".

The configuration of the latching surface of the main latch 6'! is such that it will not, by itself, retain the operating mechanism in closed position. An auxiliary latch 85 is provided to maintain the main latch 67 in latching position. The auxiliary latch 85 is pivoted on a pivot pin 81 supported in the projection 'II of the casting II and a latching projection 89 thereof is biased by means of a spring EI into latching engagement with a tail S3 of the main latch.

The auxiliary latch 85 is provided with a horizontally extending portion 35 the free end of which is disposed directly above and in alignment with a vertically disposed trip rod 91 forming a part of the trip device I9. The trip device includes, in addition to the trip rod $1, a trip magnet comprising an E-shaped magnet core 99 supported by means of a pair of brackets IOI on the under side of a projection I63 of the casting I I, the brackets i9! being suitably secured to the projection H33. An energizing coil I01 surrounding the center leg of the core 89 and suitably supported in the magnet frame, is provided to energize the trip magnet. A movable armature I39 secured on the lower end of the trip rod 91 cooperates with the magnet core 95 when the coil i6? is energized to thrust the trip rod upwardly to effect tripping of the breaker. The downward movement of the armature I33 and of the trip rod 97 is limited by engagement with a manual trip rod I i I vertically slidably mounted in a guide sleeve ii: threadediy secured on a horizontal projection I I5 of the casting II. The vertical movement of the manual trip rod I I I is limited by mean o an annular collar (not shown) thereon shoulder (also not shown) formed on the inn 1' wall of the sleeve H3. The sleeve H3 is locked in position by means of a lock nut II'I.

Upon energization of the trip device IS the armature M19 is attracted thrusting the trip rod 91 upwardly. The trip rod, at this movement, engages the portion 95 of the auxiliary latch and rocks this latch clockwise to disengage the latching projection 89 thereon from the tall 93 of the main latch fi'l. The upward force exerted on the operating rod 419 and the lever 53 by the breaker accelerating spring 52 overcomes the relatively weaker spring 73 and forces the main latch 6 clockwise the lever 53 rotates clockwise about the pivot 55 to open position. As soon as the roller 35 escapes the latch 51, the spring I3 acts to restore the latch to its latching position. When this occurs the spring EI tends to move the latch 35 to latching engagement with the main latch. Should this occur it is obvious that the latch roller 65 could not be restored to iatohing engagement with the main latch 61. In order to prevent the auxiliary latch from reengaging the ma. latch following a tripping operation and until. the mechanism is restored to full closed position a holding lever H9 is provided. Th holding lever I I9 comprises a U-shaped lever pivotally supported on the pivot pin 81 and having the two arms thereof rigidly joined at their free ends by a cross bar I2I. A spring I23, seated in a spring seat in the casting I I biases the cross iar I2I into contact with the latch roller 65 so that, when the lever 53 and the roller 85 move opening direction the spring I23 causes the holding lever II?) to rotate in a clockwise direction about the pivot 87. During this movement of the holding lever a lateral extension I25 thereon engages the portion 95 of the auxiliary latch 85 and, since the spring IE3 is relatively stronger than the spring 9!, holds the auxiliary latch in its unlatching position until the breaker is closed. When the trip device is operated to release the operating lever 53, the accelerating spring 52 moves the operating rod upwardly as the breaker mechanism moves to open position. Due to the connecting link 43 (Fig. 2) the piston Il moves therewith to the top of the cylinder I5. In order that the piston I! may move rapidly upwardly in the cylinder to provide for high-speed interruption of the circuit the dump valve mechanism indicated generally at 25 (Fig. 2) is provided and is energized simultaneously with the energization of the trip device I9 (Fig. 1). The dump valve mechanism is supported on housing I21 (Fig. 2) secured to the side of the main casting II by means of bolts (not shown). The housing I21 is provided with a passage I3I which is in alignment with an exhaust passage I33 in the wall of the cylinder I5. The exhaust passage I3I is normally closed by means of an electro magnetically operated piston valve I35 disposed for vertical movement in a cylinder I31 formed integral with the housing I21.

An electromagnet, indicated generally at I39 (Fig. 2), is provided to initiate movement of the dump valve 835 to open position. The electromagnet 339 is energized simultaneously with the trip device. The electromagnet I39 includes a U-shaped stationary core MI of laminated magnetic material supported by means of angular brackets I43 from the lower flanged end I44 of the cylinder Iil. The brackets Hi3 are secured on opposite sides oi the lower end of the stationary core Mi. Screws ME pass through each end of each of the brackets Hi3, through brackets 14'! secured to the upper end of the core ll and threadedly engage tapped holes in the flanged lower end M-i of the exhaust valve cylinder I31. Spacers I59 surround the screws Hi5 between the brackets I l! and the cylinder it? to properly locate the magnet core.

An energizing coil lei mounted between insulating members 53 is suitably supported on the brackets ill. The coil I5! is provided with a suitable central opening to receive a movable core i5I of laminated magnetic material pivotally supported on a yoke I65 secured to the lower end of a piston rod I61. The upper end of the rod iii! passes loosely through the head of the valve Hi5, and is headed. as at I83 and operatively engages the closed end of the cup-like piston valve i3b.

The valve I35 and the movable core Iii! are biased to the closed position by a coil spring I'H compressed between a washer lid, supported on the brackets IN, and the head of the valve l35.

As was stated previously the exhaust valve magnet I33 is energized simultaneously with the trip device 39 (Fig. 1), and when energized, attracts the movable core 565 (Fig. 2) drawing the valve I35 downwardly in the cylinder I31 to slightly open the exhaust passages lei. On tripi'ree operations, that is, when the breaker is closed in against a fault, the compressed air in the breaker operating cylinder above the piston IT, at the time the dump valve M55 is opened by the electromagnet m9, will push the exhaust valve down to its full open. position thereby quickly dumping the air from the cylinder to permit quick reversal of the mechanism and movement of the breaker to open position. As the breaker moves to open position drawing the piston i1 upwardly in the cylinder I5, the air above the piston is quickly exhausted to the atmosphere through the relatively large passage l33I3I.

As the piston i1 travels upwardly it passes the exhaust port after which the air trapped above the piston is compressed to absorb the kinetic energy of the moving mass of the breaker. The trapped air is vented to the atmosphere through a passage I (Figs. 2 and 3) extending vertically through the upper portion 33 of the casting I! and into an extension I'Il thereof, a horizontal passage I78 connecting with the upper end of the vertical passage, horizontal passages I86, N32 and HM to the atmosphere. The passages I82 and I8 3 are formed in the housing it! of the inlet valve, the passage I84 being controlled by a valve I93 disposed therein and operated by the electromagnet IS! in a manner to be fully described later.

On normal opening operations, while the electrorna-gnet' 33 is energized with. the trip device and partly opens the dump valve I35, there is no compressed air in the cylinder to move the valve I 35 to full open position, consequently the valve returns to closed position upon deenergization of the electromagnet ltd. During a normal opening operation the air in the cylinder above the piston is exhausted through the passage comprising the passages Il5, lit, I89, I32 and I84 (Fig.3).

The circuit breaker may be manually tripped open by energizing the electrical circuit for the trip device by means of a manually controlled switch (not shown). The circuit breaker may be tripped open mechanically in case of failure of current in the control circuit (not shown) by manually operating the trip rod 9? (Fig. 1). This is accomplished by operating a bell crank I94 (Fig. 1) pivotally supported by means of a pivot pin I mounted in a bracket I86 secured to the under side of the projection H5 which supports the manual trip rod III. The bent end I88 of a pull rod Ifiil projects through an opening in an ear 592 of the downwardly extending arm of the bell crank I84 and is suite. ly retained in place by a cotter pin.

When it is desired to tripthe breaker mechanithe pull rod ass is drawn toward the left l) which rotates the bell crank I94 clockwise thru ting the manual trip rod and the trip rod v'ardly to operate the latch mechanism The circ breaker then moves to the open above the operating piston I! being e..pelled to atmosphere from the cylinder through the fully open passages H5, I18, I80,

iiii (Figs. 2 an d 3) since the dump magnet i353 is not energised upon mechanical operation of the trip device.

In order to close he breaker Ell (Fig. 1) compressed is to th cylinder i5 above the piston li hrough the inlet passage I'M-I75 by operation of the inlet valve mechanism 2!. The ll. t valve mechanism includes the housing I8I which securely mounted by means of bolts its (Fig. 3) the side of the extension IT! of the main casting. An inlet valve it? disposed for vertical movement within the housing I BI, is biased to closed oos' ion by means of a spring it"! seated on an inlet chamber i353 suitably secured to the bottom of the housing 33!. The upper oi? the i id; bears against the valve 8%. The vs vve 55233 is secured on a rod lei which also carries the exhaust valve I93. When the inlet valve closed the exhaust valve ltd is open connecting the upper end of the operating cylinder to the atmosphere through the previously described passage. When let valve is operated to open position the i to ad; it compressed air to the cylinder I5 the valve ltd is moved to close the exhaust passage I84.

ihe inlet and the exhaust valve I93 are operated to open position and closed position by means of the electromagnet indicated. generally at itl. The magnet It! includes a U-shaped stationary core member ita of laminated construction supported on a plate 2M by means of angular brackets Zed suitably see red, for instance, by welding, to the core member. The brackets are secured to the plate ZilI which, in turn, is secured to the top of the inlet valve housing lei by of screws An energizing coil 2&9 is mounted between insulating plates 2H secured to the core member lbs. The lower portion of the core member is? is provided with a clearance opening (not shown) through which the valve stem it! passes, and the coil 209 has a central opening (also not shown) in which is disposed a T- haped movable core 2 I1.

The control circuits for the trip device I9 and the inlet valve electromagnet I91 are preferably the same as he control circuits disclosed in the copending application of James M. Cumming and Richard C. Cunningham, Serial No. 410,686, filed September 13, 1941, now Patent No. 2,408,199, issued September 24, 1946, and assigned to the assignee of the present invention. The control circuits have not been shown in this case as they are not necessary for a complete understanding of the present invention. It is believed sufiicient for the purpose at hand to mention that the inlet valve electromagnet may be energized in response to the operation of a manual closing control switch or automatically in response to the closing of an auxi 'ary switch which may be set to close at an intermediate position in the opening stroke of the breaker so as to initiate quick reclosing of the breaker. The trip device I9 is energized in response to an overload or other fault condition. For details or the control circuits reference may be had to the aforementioned copending application. As previously pointed out the exhaust valve electroinagnet I39 is energized simultaneously with the trip device When the electromagnet I91 is energized, the magnet attracts the movable core 2!! which thrusts the valve stem I9I downwardly closing the exhaust valve I93 and opening the inlet valve I85. The inlet air chamber I86 is connected by means of a pipe 2 I9 (Figs. 2 and 3) to a source (not shown) of compressed air. When the inlet valve I85 (Fig. 2) is opened air under pressure is admitted through the passage I19I 15 to the upper end or" the operating cylinder I moving the piston i1 toward the bottom of the cylinder and moving the connected breaker operating mechanism to closed position.

The driving force required for normal closing operations where the closing movement is initiated from the full open position is much less during the first portion of the closing stroke than during the portion of the closing stroke when the heavy contact load is being overcome, and is also much less than that required to quickly reverse the switching movement and automatically reclose the breaker after interruption of the circuit and before the br aker reaches full open position. The automatically operable valve 23 (Fig. 2) is effective to reduce the flow of compressed air adnitted to the operating cylinder during the first part of the closing stroke on normal closing operations, but permits the full fiow of air pressure to the cylinder during the final portion of the closing stroke. The valve 23 is also effective to permit full flow of compressed air during quick reclosing operations to provide additional power required to quickly reverse the movement of the breaker and quickly reclose the same.

The rate of flow of compressed air to the cylinder I5 to effect closing of the circuit breaker is controlled by the previously mentioned valve 23 and by an adjustable metering pin 22I (Fig. 3) in an auxiliary air passage. The valve 23 includes a piston type valve 223 (Figs. 2 and 3) disposed for vertical movement in a cylinder formed in the projection I11 of the main casting. The valve 223 is cup-shaped and has an operating rod 221 integral therewith and extending vertically beyond the valve through an opening in a guide bracket 229. The bracket 229, which is suitably secured to the top of the extension I11 also serves to limit the upward or closing movement of the valve. A spring 233 disposed in the hollow valve and seated in the bottom or the valve cylinder biases the valve 223 in closing direction and moves the valve to closed position as the breaker moves to open position.

The valve 223 is restrained in open position when the breaker is closed and is adapted to be moved downwardly to open position as the breakor mechanism approaches closed position by means of a tappet 231 (Figs. 1 and 2) secured by means of bolts 239 to an angle bracket 24I which is ecured by means of welding to the adjacent operating lever 53.

The valve 223 is shown in Fig. 2 in the open position in which an annular groove 245 on the outer periphery of the valve is in alignment with the passages I15 and I19 thereby connecting these passages to admit a full flow of compressed air to the operating cylinder I5.

The metering pin 22I is disposed in an opening 255 (Fig. 3) in the casting I11, which forms part of a bypass channel 251 connecting the passage I15 through an offset passage 259 to the passage I19. The metering pin 22I threadedly engages the opening 255 in the casting and is adjustable by rotating it in either direction to move the inner end thereof relative to the channel 251 to thereby regulate the flow of air through the bypass channel around the valve 223 and independently of the valve. A look nut 26I is provided to lock the metering pin in its adjusted position.

Early in the upward movement of the valve 223 the groove 245 is moved out of alignment with the passages I15 and I19 thus blocking these passages. Thereafter, during the opening stroke of the piston I1, the air in the top of the cylinder I5 escapes to atmosphere through the bypass channel I15, I18, I82, I84 and the bypass channel 255, 251 and 259 under the control of the metering pin Hi. The rate of flow of compressed air into circuit breaker operating cylinder through the inlet passage I19, 251, 255 is adjusted by means of the metering screw 22I (Fig. 3) which controls the size of the passage through which air is admitted to the operating cylinder. This metering screw is adjusted to obtain the desired closing speed of the breaker. The size of the restricted inlet passage 255-251 is too small to permit high-speed venting of the compressed air trapped above the piston on opening operations. The size of the exhaust passage I18, I80, I82, I84 is uch that rapid and full venting of the cylinder is obtained. The air back of the piston, however, is compressed sufilciently to cushion the final opening movement of the piston and the breaker mechanism.

When the closing magnet I91 (Fig. 2) is energized to initiate a closing movement of the operating mechanism, it closes the exhaust valve I93 (Fig. 2) and opens the inlet valve I85. This admits compressed air from the source (not shown) through the inlet chamber I86, inlet valve I85, passage I19, bypass channel 259, 251 and 255 (Fig. 3) and the passage I15 to the upper end of the operating cylinder I5 above the piston I1. This forces the piston downwardly and moves the connected operating mechanism toward closed position, the meterin pin 22I acting to throttle the flow of air to the cylinder a predetermined amount. As the piston I1 (Fig. 2) moves downwardly in the cylinder, the lever 53 is rotated in a counterclockwise direction (Fig. 1)

and, at a predetermined time during this movement, the tappet 23'! engages the upper end of the valve rod 221 and moves the valve 223 downwardly to its lower or open position in which the groove 245 is aligned with the passage [75-419. This occurs shortly before the breaker contacts engage, thus providing an increased volume of compressed air to bring the movable contacts quickly into pressure engagement with the stationary contacts.

The valve 223 is automatically controlled by the operating lever 53 according to the position of the breaker in such a manner that the valve will remain in its open position upon a quick automatic reclosing operation when the reclosing movement of the breaker is initiated when the breaker is in an intermediate or partially open position. Thi provides for the admission of a full volume of compressed air to the operating cylinder in order to quickly reverse the movement of the operating piston and breaker operating mechanism and to operate said mechanism to fully closed position.

From the foregoing it will be apparent that the valve mechanism provides for quick reversal of movement of the circuit breaker and piston and high-speed opening movement of these parts because of the rapid venting of the cylinder through the passage controlled by the exhaust valve 953. The throttle valve 223 together with the adjustable inlet passage 255-251 reduces the flow of com-pressed air admitted to the operating cylinder during the first part of the closing stroke on normal closing operations to prevent slamming of the parts but permits the full flow of compressed air to the cylinder during the final heavy load of the closing stroke.

While the invention has been disclosed in accordance with the provisions of the patent statutes, it is to be unders ood that various changes in the structural details and arrangement of parts thereof may be made Without departing from some of the essential features of the invention. It is desired, therefore, that the language of the appended claims be given the broadest reasonable construction permitted in the light of the prior art.

I claim as my invention:

1. In a circuit interrupter having relatively movable contacts, comprising a cylinder, an operating piston in said cylinder operatively related With said circuit interrupter, a source of compressing a control valve device associated with-said cylinder for admitting compressed gas to said cylinder for operating said piston in one direction and for rapidly venting said cylinder directly to atmosphere to permit high-speed reverse movement of said piston, said valve device having an inlet passage connected to said cylinder, an exhaust passage communicating with the cylinder independently of said inlet passage for rapidly venting said cylinder directly to atmosphere, an inlet valve biused to normally close said inlet passa e, an exhaust valve biased to normally open said exhaust passage, actuating means for said valves comprising an electromagnet operable to move said inlet valve to open position and to move said exhaust valve to closed position, a control valve disposed in said inlet passage between said inlet valve and said cylinder, said control valve being operable by the breaker mechanism to reduce the amount of compressed gas admitted to said cylinder to effect closing of said interrupter from a full open position, adjusting means for varying operating means therefor at will the minimum amount of compressed gas admitted to the cylinder to close the breaker from full open position and said control valve being operable during the closing movement to increase the amount of compressed gas admitted to the cylinder near the end the closing movement of the interrupter.

2. An operating mechanism of the pneumatic type for operating an electrical circuit interruptor comprising a cylinder, a piston movable in said cylinder and operatively related with the circuit interrupter, a source of compressed gas, a control valve device for admitting compressed gas to said cylinder to move said piston in one direction to operate said interrupter and for also rapidly venting said cylinder directly to atmosphere, said valve device having an inlet passage communieating with said cylinder, a control valve disposed in said inlet passage, said control valve being operable to reduce the amount of compressed gas admitted to said cylinder to effect closing of the interrupter from full open position, means operable during the opening stroke for operating said control valve to admit a full flow of compressed gas to said cylinder near the end of the closing operation, a bypass channel around said automatic valve for rapidly venting said cylinder to atmosphere independently of said control valve, an inlet valve biased to a closed position to close oil said inlet valve from said source, an exhaust valve biased to open said exhaust passage, and actuating means operable when energized to close the exhaust valve and open said inlet valve.

3. An operati" g mechanism for an electrical erating piston in said cylinder for operating said interrupter, a source of compressed gas, a control valve device for admitting compressed gas to said cylinder to move the piston in one direction to operate said interrupter and for rapidly venting said cylinder directly to atmosphere to permit high-speed reverse movement of said piston, said valve device having an inlet passage connected to said cylinder, an exhaust passage for rapidly venting said cylinder directly to atmosphere independently of said inlet passage, valve means associated with said passages having a normal position closing said inlet passage and opening said exhaust passage, spring means biasing said valve means to said normal position, actuating means operable when energized to move said valve means to open said inlet passage and close said exhaust passage, a control valve disposed in said inlet passage automatically operable when said interrupter moves to open position to reduce the amount of compressed gas admitted to said cylinder, and means comprisin a bypass channel around said control valve for admitting a predetermined amount of compressed gas independently of said control valve to effect normal closing operation from full open position said control valve being operable to admit a full flow of compressed gas near the end of the closing operation and also to admit a full flow of compressed gas to effect high-speed reverse movement of said piston.

4. An operating mechanism for an electrical circuit interrupter comprising a cylinder, an operating piston movable in said cylinder for opera'ng said interrupter, a source of fluid under control valve means for admitting fluid pressure to said cylinder and for quickly venting cylinder to atmosphere, said valve means having an inlet passage, an inlet valve, means normally biasing said inlet valve to close said inlet passage, an electromagnet operable when energized to operate said inlet valve to open said inlet passage, a control valve disposed in said inlet passage and operable upon opening movement of said interrupter to reduce the amount of fluid pressure admitted to said cylinder on normal closing operations, adjustable means associated with said inlet passage to vary the rate of flow of the fluid pressure admitted to said cylinder, an exhaust passage bypassing said control valve, an exhaust valve biased to open said exhaust passage for rapidly venting said cylinder to atmosphere independently of said control valve, said exhaust valve being operable by said electromagnet to close said exhaust passage, and means for operating said control valve to cause a full flow of compressed fluid to be admitted to said cylinder during the latter portion of the closing movement of the interrupter.

5. An operating mechanism for a circuit interrupter comprising a fluid motor operable to close said interrupter, an inlet valve disposed in an inlet passage and operable to admit fluid pressure to said motor to effect closing of said interrupter, a control valve disposed in said inlet passage and operable at a predetermined time during an openin movement of said interrupter to substantially close said inlet passage, means comprising an auxiliary inlet passage for admitting fluid pressure at a predetermined rate to said motor to effect closing of the interrupter from full open position, an exhaust passage bypassing said inlet passages for rapidly venting said cylinder to atmosphere, an exhaust valve biased to open said exhaust passage, means operable to close said exhaust valve and open said inlet valve, and means operable durin the closing operation for opening said control valve to cause greater fluid pressure to be applied to the motor near the end of the closing operation than at the beginning of the closing operation.

6. In an operating mechanism for a circuit breaker, an operatin cylinder, a piston in said cylinder for moving said breaker to closed position, an inlet passage connecting said cylinder to a source of compressed gas, an exhaust passage connecting said cylinder to atmosphere, inlet and exhaust valves associated with said passages, means biasing said valves to normally open said exhaust passage and to close said inlet passage, electroresponsive means for simultaneously operating said valves to close said exhaust passage and open said inlet passage to thereby effect closing of said breaker, a control valve disposed in said inlet passage and operable to close said passage at a predetermined intermediate point in the opening movement of the breaker, means comprising a channel bypassing said control valve for admitting independently of said control valve a predetermined amount of compressed gas to the cylinder to close the breaker, adjustable means disposed in said bypass channel for adjustably determining the amount of compressed gas to be admitted to said cylinder to initiate closing movement of the breaker, and means operable during the closing movement of the breaker to cause opening of said control valve to thereby increase the amount of compressed air admitted to the cylinder at a predetermined intermediate point in the closing movement of the breaker.

'7. An operating mechanism for a circuit breaker comprising a cylinder and a piston movable therein for moving said breaker to closed position, a trip device operable to cause opening of the breaker, an inlet valve biased closed and operable to admit compressed air to said cylinder to close said breaker, an inlet passage connectin said inlet valve and said cylinder, a control valve disposed in said inlet passage between said inlet valve and said cylinder and operable to close said inlet passage at a predetermined intermediate point in the opening movement of the breaker, an exhaust passage bypassing said inlet passage and said control valve for rapidly ventin said cylinder directly to atmosphere independently of said control valve, an exhaust valve biased to open said exhaust passage, actuating means operable when energized to close said exhaust valve and open said inlet valve, and means operable by a closing movement of said breaker to open said control valve to thereby admit a full flow of compressed gas to said cylinder near the end of the closing stroke.

8. In an electrical circuit breaker having movable contact means, operating means for said breaker comprising spring means biasing said breaker to open position, latching means for holding said circuit breaker closed, an operating cylinder, an operatin piston in said cylinder nonreleasably connected to the movable contact means for closing the circuit breaker, a source of compressed gas, a control valve device associated with said cylinder for admitting compressed gas to said cylinder for actuating said piston to close the breaker and for also rapidly venting said cylinder directly to atmosphere to permit high-speed opening of the circuit breaker, said control valve device having an inlet passage connected to said cylinder, an exhaust passage by passing said inlet passage for rapidly venting said cylinder directly to atmosphere connected to said cylinder, an inlet valve biased to closed position to close said inlet passage, an exhaust valve biased to open said exhaust passage, spring means biasing said inlet valve closed and said exhaust valve open, valve actuating means comprising an electromagnet operable when energized for closing said exhaust valve and opening said inlet valve to admit compressed gas to said cylinder, a control valve disposed in said inlet passage intermediate said inlet valve and said cylinder for controlling the amount of compressed gas admitted to said cylinder and an auxiliary inlet passage bypassing said control valve for admitting a predetermined amount of compressed gas irrespective of said control valve.

9. In an electrical circuit breaker having movable contact means, operating means for said breaker comprising spring means biasing said breaker to open position, latching means for holding said circuit breaker closed, an operating cylinder, an operating piston in said cylinder nonreleasably connected to the movable contact means for closing the circuit breaker, a source of compressed gas, a control valve device associated with said cylinder for admitting compressed gas to said cylinder for actuating said piston to close the breaker and for also rapidly venting said cylinder directly to atmosphere to permit highspeed opening of the circuit breaker, said control valve device having an inlet passage connected to said cylinder, an exhaust passage independent of said inlet passage for rapidly venting said cylinder directly to atmosphere connected to said cylinder, an inlet valve biased to closed position to close said inlet passage, an exhaust valve biased to open said exhaust passage, spring means biasing said inlet valve closed and said exhaust valve open, valve actuating means comprising an electromagnet operable when energized for closing said exhaust valve and opening said inlet valve to admit compressed gas to said cylinder, a control valve disposed in said inlet passage intermediate said inlet valve and said cylinder for controlling the amount of compressed gas admitted to said cylinder, said control valve being operable to reduce the amount of compressed gas admitted to the cylinder on normal closing operations and to increase the amount of compressed gas admitted to the cylinder near the end of the closing movement and means for adjustably determining the minimum amount of compressed gas admitted to the cylinder on normal closing operations.

10. An operating mechanism for a circuit breaker comprising a cylinder, an operating piston in said cylinder for operating said circuit breaker, a source of compressed gas, an inlet passage communicating with said cylinder, an exhaust passage for rapidly venting said cylinder directly to atmosphere, an inlet valve biased to closed position to close said inlet passage, an exhaust valve biased to open said exhaust passage, actuating means operable when energized to close said exhaust valve and open said inlet valve, a normally open control valve disposed in said inlet passage biased to closed position and automatically operable upon movement of said breaker to open position to substantially close said inlet passage, an auxiliary inlet passage bypassing said control valve for admitting a predetermined amount of compressed gas to the cylinder independently of said control valve to effect closing or the breaker from full open position, and means operable during a closing movement of the breaker to open said control valve to thereby increase the flow of compressed gas to the cylinder near the end of the closing stroke.

GILBERT J. EASLEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

